Magnetospheric–Ionospheric–Lithospheric Coupling Model. 1: Observations during the 5 August 2018 Bayan Earthquake

Abstract

The short-term prediction of earthquakes is an essential issue connected with human life protection and related social and economic matters. Recent papers have provided some evidence of the link between the lithosphere, lower atmosphere, and ionosphere, even though with marginal statistical evidence. The basic coupling is hypothesized as being via the atmospheric gravity wave (AGW)/acoustic wave (AW) channel. In this paper we analyze a scenario of the low latitude earthquake (Mw = 6.9) which occurred in Indonesia on 5 August 2018, through a multi-instrumental approach, using ground and satellites high quality data. As a result, we derive a new analytical lithospheric–atmospheric–ionospheric–magnetospheric coupling model with the aim to provide quantitative indicators to interpret the observations around 6 h before and at the moment of the earthquake occurrence.

On the Geomagnetic Field Line Resonance Eigenfrequency Variations during Seismic Event

“…Indeed, both these phenomena would be able to generate changes in atmospheric temperature and hence AGW formation (e.g., [39]). A similar result was found in Piersanti et al [16] who found a decrease of f * 5 h before the EQ occurrence. They explained their observation in terms of the M.I.L.C.…”

“…In fact, depending on the characteristic parameters of the EQ (length of the fault, peak ground acceleration strong time duration and so on), a the propagation of the AGW up to the ionosphere can be prevented. In order to confirm such hypothesis, for these events, we analyzed the vertical atmospheric temperature profiles using the approach described in Piersanti et al [16] to catch for possible AGW injection. Here, we display the analysis of the 19/12/2006 Sumatra EQ, since the remaining nine case events show similar results.…”

“…In 28 events, we found a clear sudden decrease of the magnetospheric FLR eigenfrequencies, while in 10 cases we did not find any f * variation. The proposed explanation is that the plasma density at the footprint of the field line magnetically connected to the EQ location was modified of about ∆ρ 15%, by a gradient pressure fluctuations ∇p den induced by a propagation of an AGW emitted during the EQ occurrence [15,16]. At low latitudes the magnetospheric field lines are fully surrounded by the ionosphere and the FLR eigenfrequencies, depending on both the magnetic field and the plasma density along the field line [19,31], is expected to decrease [23,26,32].…”

“…Searches for possible seismo-ionospheric effects were also performed before the earthquake by the satellite Interkosmos-19 operating at F-region altitudes, providing for the first time evidence for an increase of both the intensity of VLF noise, in the frequency range between 140 Hz to 15 kHz, and for disturbances of the electron density at a distance from the epicentres up to a few 1000 km [3,14]. More recently, Carbone et al [15], Piersanti et al [16] started the development of an analytical model of the coupling between lithosphere-atmosphere-ionosphere-magnetosphere to be submitted to detailed experimental verification (M.I.L.C.). In the M.I.L.C.…”

Trapped Proton Fluxes Estimation Inside the South Atlantic Anomaly Using the NASA AE9/AP9/SPM Radiation Models along the China Seismo-Electromagnetic Satellite Orbit

“…and long time-scales (i.e., cosmic-ray propagation, composition, etc.) [26,27]. A recent perspective [28] explained that claims based on self-organized criticality stating that at any moment any small earthquake can eventually cascade to a large event do not stand in view of the results obtained by natural time analysis [29,30].…”